powerpc/inst: Reduce casts in get_user_instr()

Declare __gui_ptr as 'u32 *' instead of casting it at each use to
'unsigned int *' (which is an equivalent type).
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[mpe: Use u32 * instead of unsigned int *]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/2c2123998e05535d08ba03a96ea1eea921d06a86.1621516826.git.christophe.leroy@csgroup.eu

arch/powerpc/include/asm/inst.h

@@ -9,16 +9,15 @@
 #define ___get_user_instr(gu_op, dest, ptr)				\
 ({									\
 	long __gui_ret = 0;						\
-	unsigned long __gui_ptr = (unsigned long)ptr;			\
+	u32 __user *__gui_ptr = (u32 __user *)ptr;			\
 	struct ppc_inst __gui_inst;					\
 	unsigned int __prefix, __suffix;				\
 									\
 	__chk_user_ptr(ptr);						\
-	__gui_ret = gu_op(__prefix, (unsigned int __user *)__gui_ptr);	\
+	__gui_ret = gu_op(__prefix, __gui_ptr);				\
 	if (__gui_ret == 0) {						\
 		if ((__prefix >> 26) == OP_PREFIX) {			\
-			__gui_ret = gu_op(__suffix,			\
-				(unsigned int __user *)__gui_ptr + 1);	\
+			__gui_ret = gu_op(__suffix, __gui_ptr + 1);	\
 			__gui_inst = ppc_inst_prefix(__prefix,		\
 						     __suffix);		\
 		} else {						\